JP2016140918A - robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a robot capable of enlarging a working range while suppressing increase in size of an apparatus.SOLUTION: A robot 1 comprises: a base 3; a slewing part 5 attached to the base 3 in a manner to slew on a first axis Ax1 substantially normal to an installation face on which the base 3 is installed; an arm 7 oscillatably attached to the slewing part 5 for oscillating on a second axis Ax2 horizontal to the installation face; a first motor 20 housed in the slewing part 5 for actuating the slewing part 5 on the first axis Ax1 against the base 3; and a second motor 20 for operating the arm 7 on the second axis Ax2 against the slewing part 5. The first motor 20 includes: a body part 30 shaped to have a smaller size in the output axis Ax than the size substantially perpendicular to said output axis Ax; and a projection 70 protruding from one face 30b of the body part 30 along the direction of the output axis Ax and arranged at a position deviated from the output axis Ax.SELECTED DRAWING: Figure 4

Description

  The present disclosure relates to a robot.

  Patent Document 1 discloses a base, a swing base that swings around the S axis with respect to the base, a lower arm that swings around the L axis with respect to the swing base, and a swing around the U axis with respect to the lower arm. An industrial robot having a moving upper arm is disclosed. The turning base is operated by a motor arranged coaxially with the S axis, the lower arm is operated by a motor arranged coaxially with the L axis, and the upper arm is operated by a motor arranged coaxially with the U axis. .

Japanese Patent Laid-Open No. 2003-200376

  In a robot, in order to perform work over a wide range, an expansion of an operation range is required. In order to expand the operation range in the robot, it is effective to increase the swing angle of the lower arm that is swingably attached to the turning base. However, the swing angle of the lower arm is limited because it is set to avoid contact between the turning base and the lower arm. Therefore, in order to enlarge the swing angle of the lower arm, it is necessary to avoid contact between the turning base and the lower arm. For this purpose, the position of the L axis is set at a higher position than the turning base. It is necessary to lower the height of the turning base by arranging the output shaft of the motor that operates the turning base so as to be shifted from the S axis. However, in any configuration, there is a problem that the apparatus becomes large.

  An object of the present disclosure is to provide a robot capable of expanding an operation range while suppressing an increase in size of the apparatus.

  A robot according to one aspect of the present disclosure includes a base, a turning unit that is turnably attached to the base, and that turns about a first axis in a direction substantially perpendicular to an installation surface on which the base is installed, and a turning unit An arm that swings about a second axis that is horizontal to the installation surface, a first motor that is housed in the swivel unit and moves the swivel unit about the first axis relative to the base, A second motor that moves the arm around the second axis with respect to the swivel unit, and the first motor has a body whose dimension in the output shaft direction is smaller than the dimension in the direction substantially perpendicular to the output shaft And a protrusion that protrudes from one surface of the main body along the output shaft direction and is disposed at a position shifted from the output shaft.

  According to the present disclosure, the operating range can be expanded while downsizing.

FIG. 1 is a perspective view showing a robot according to an embodiment. FIG. 2 is a side view of the robot shown in FIG. FIG. 3 is a view of the robot shown in FIG. 1 viewed from behind. FIG. 4 is a perspective view showing the appearance of the motor. FIG. 5 is a diagram showing a cross-sectional configuration of the motor. FIG. 6 is a diagram illustrating an internal configuration of the base portion and the turning portion. FIG. 7 is a diagram showing the arrangement of the motor.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements will be denoted by the same reference numerals, and redundant description will be omitted.

[Robot configuration]
FIG. 1 is a perspective view showing a robot according to an embodiment. FIG. 2 is a side view of the robot shown in FIG. FIG. 3 is a view of the robot shown in FIG. 1 viewed from behind. A robot 1 shown in each figure is an industrial robot that performs work on a workpiece (not shown).

  As shown in FIGS. 1 to 3, the robot 1 includes a base 3, a turning unit 5, a first arm 7, a second arm 9, and an end base 11. The base 3, the turning unit 5, the first arm 7, the second arm 9, and the end base 11 are connected in this order from the base end to the tip end of the robot 1.

  The base 3 is fixed to the installation surface and supports the entire robot 1.

  The swivel unit 5 is provided on the base 3. The turning unit 5 can turn around the first axis Ax1 with respect to the base 3 with the first axis Ax1 extending in the vertical direction as a turning axis. The turning unit 5 is driven using the first motor housed in the turning unit 5 as a power source, and turns around the first axis Ax1. The first axis Ax1 may be referred to as the S axis.

  The first arm 7 swivels about the second axis Ax2 passing through the swivel unit 5 and the connecting portion 6 of the first arm 7 (the end of the first arm 7 on the swivel unit 5 side) as a swing axis. The part 5 can swing around the second axis Ax2. A second motor is mounted on the connecting portion 6 of the turning unit 5 and the first arm 7.

  The first arm 7 is driven using a second motor as a power source, and swings around a second axis Ax2 that is horizontal to the installation surface. Specifically, as shown in FIG. 6, the first arm 7 has a first direction D1 (front) with respect to a reference line LS that is substantially perpendicular to the installation surface and passes through the second axis Ax2. The first swing angle θ1 can be swung. The first arm 7 has a second swing angle θ2 (θ1> θ2) smaller than the first swing angle θ1 in the second direction D2 (backward) opposite to the first direction D1 with respect to the reference line LS. It can be swung up to. When viewed from the direction along the second axis Ax2, the first axis Ax1 is located on the second direction D2 side with respect to the reference line LS. The second axis Ax2 may be referred to as the L axis.

  The second arm 9 has a proximal end portion 9a located on the first arm 7 side and a distal end portion 9b located on the end base 11 side. The base end portion 9a has a third axis Ax3 passing through the connecting portion 10 of the first arm 7 and the second arm 9 (the end portion on the base end portion 9a side of the first arm 7) as a swing axis. The first arm 7 can be swung around the third axis Ax3. Therefore, the second arm 9 as a whole can swing around the third axis Ax3 with respect to the first arm 7. A third motor is mounted on the connecting portion 10 of the first arm 7 and the second arm 9. The second arm 9 (base end portion 9a) is driven by using the third motor as a power source and swings around the third axis Ax3. The third axis Ax3 extends in parallel with the second axis Ax2. The third axis Ax3 may be referred to as the U axis.

  The distal end portion 9b can pivot about the fourth axis Ax4 with respect to the base end portion 9a with the fourth axis Ax4 passing through the center of the second arm 9 as a pivot axis. The distal end portion 9b is driven using the fourth motor as a power source, and turns around the fourth axis Ax4. The fourth axis Ax4 may be referred to as the R axis.

  The end base 11 has a proximal end portion 11a located on the second arm 9 side and a distal end portion 11b located on the distal end side. The proximal end portion 11a is fifth relative to the distal end portion 9b with a fifth axis Ax5 passing through the connecting portion of the second arm 9 (tip end portion 9b) and the end base 11 (base end portion 11a) as a swing axis. Can be swung around the axis Ax5. The base end portion 11a is driven using the fifth motor as a power source, and swings around the fifth axis Ax5. The fifth axis Ax5 may be referred to as the B axis.

  The distal end portion 11b is attached to the base end portion 11a so as to be rotatable around the sixth axis Ax6, with the sixth axis Ax6 passing through the center of the end base 11 as a rotation axis. The distal end portion 11b is driven using the sixth motor as a power source and rotates around the sixth axis Ax6. The sixth axis Ax6 may be referred to as the T axis. An end effector is attached to the end base 11. The end effector is, for example, a welding torch.

[Motor configuration]
Next, the first to sixth motors mounted on the robot 1 will be described in detail. The first to sixth motors have the same configuration. Hereinafter, it may be simply referred to as a motor. FIG. 4 is a perspective view showing the appearance of the motor. FIG. 5 is a diagram showing a cross-sectional configuration of the motor. As shown in FIGS. 4 and 5, the motor 20 includes a casing (main body part) 30, a rotor 40, a stator 50, an encoder 60, and a brake (protrusion part) 70.

  The casing 30 holds the rotor 40, the stator 50, the encoder 60, and the like. The outer shape of the casing 30 has, for example, a circular shape. The casing 30 includes a first surface (other surface) 30a and a second surface (one surface) 30b orthogonal to the output shaft Ax of the motor 20, and a circular third surface 30c extending along the output shaft Ax. Have. The casing 30 is shaped so that the dimension in the direction along the output axis Ax of the motor 20 is smaller than the dimension in the direction substantially perpendicular to the output axis Ax. That is, the casing 30 has a flat shape in which the dimension L1 between the first surface 30a and the second surface 30b is smaller than the dimension L2 corresponding to the diameter of the opposing third surface 30c (L1 <L2). Yes. In this embodiment, the dimension L1 is set to 1/2 or less of the dimension L2.

  The rotor 40 includes a rotating body 42 and a brake pad 44. The rotating body 42 is a member that is driven to rotate about the output shaft Ax. The rotating body 42 can be rotated by annular bearings 46 a and 46 b fixed to the casing 30. The bearings 46a and 46b are arranged side by side with a predetermined interval in the direction along the output axis Ax. Magnets 48 are arranged on the outer circumferential surface of the rotor 40 along the circumferential direction. The rotating body 42 has a shaft member 43. The shaft member 43 protrudes from the first surface 30 a of the casing 30.

  The brake pad 44 is a member that is braked by the brake 70. The brake pad 44 is provided on the peripheral edge of the rotating body 42. The brake pad 44 has an annular shape. The brake pad 44 is disposed coaxially with the output shaft Ax. The outer edge of the brake pad 44 is located outside the outer edge of the rotating body 42. That is, the outer diameter of the brake pad 44 is larger than the outer diameter of the rotating body 42. The brake pad 44 is made of, for example, metal.

  The stator 50 is a member that applies a rotational force to the rotor 40. The stator 50 has a core 52 and a coil 54. The core 52 has an annular shape, for example. The core 52 is disposed at a position facing the outer peripheral surface of the rotating body 42. The coil 54 is provided in the core 52.

  The encoder 60 is a rotation detection device that detects the rotation of the rotor 40. The encoder 60 is a rotary encoder, for example, and can detect the drive amount of the motor 20 such as the rotation speed, rotation angle, and / or rotation speed of the rotor 40. A part of the encoder 60 is disposed in the recess 42 a of the rotating body 42.

  The brake 70 is a braking device that brakes the rotation of the rotor 40. The brake 70 protrudes along the output shaft Ax from the second surface 30b of the casing 30 outward. The brake 70 is disposed at a position eccentric from the output shaft Ax. The brake 70 includes a case 72, a friction material 74, a holding member 76, an urging member 78, and a coil 79.

  The case 72 houses the holding member 76, the biasing member 78, and the coil 79. The case 72 is fixed to the casing 30 by screws, for example. As shown in FIG. 4, the outer shape of the case 72 has, for example, a cylindrical shape. The shape of the case 72 may be set as appropriate according to the design.

  The friction material 74 applies a frictional force to the brake pad 44 by slidingly contacting (contacting) the brake pad 44 of the rotor 40. The friction material 74 is provided on the holding member 76. As a material of the friction material 74, for example, a range mold, a semi-metallic material, a sintered alloy (iron-based, copper-based), or the like can be used.

  The holding member 76 holds the friction material 74. The holding member 76 is made of, for example, metal. The holding member 76 has a substantially T shape. The holding member 76 has a main body portion 76a and a holding portion 76b.

  The main body 76a has, for example, a cylindrical shape. The main body portion 76a extends in a direction along the output axis Ax. The holding part 76b has a disk shape, for example. The holding portion 76b is provided at one end of the main body 76a (the end near the brake pad 44). The outer diameter of the holding part 76b is larger than the outer diameter of the main body part 76a. The holding portion 76 b is disposed to face the brake pad 44 of the rotor 40. That is, the friction material 74 is disposed to face the brake pad 44.

  The holding member 76 is provided so as to be movable (slidable) in a direction along the output axis Ax. Specifically, the holding member 76 is movable between a first position (initial position) where the holding portion 76 b contacts the coil 79 and a second position where the friction material 74 slides on the brake pad 44. Is provided.

  The urging member 78 urges the holding member 76. The biasing member 78 is, for example, a coil spring. The biasing member 78 is disposed at the other end of the main body 76 a of the holding member 76. The urging member 78 urges the holding member 76 toward the rotor 40 when the holding member 76 is located at the first position.

  The coil 79 controls the movement of the holding member 76. The coil 79 is disposed so as to surround the main body 76 a of the holding member 76. When the current is supplied, the coil 79 applies an electromagnetic force against the urging force of the urging member 78 to pull the holding portion 76b and hold the holding member 76 in the first position. The coil 79 releases the holding member 76 when no current is supplied.

  When the supply of current to the coil 79 is stopped, the brake 70 having the above configuration releases the holding member 76 held by the coil 79 and advances the holding member 76 toward the rotor 40 by the urging force of the urging member 78. Let That is, the holding member 76 is positioned at the second position. The brake 70 brings the friction material 74 into sliding contact with the brake pad 44 and applies a frictional force to the brake pad 44. Thereby, the rotor 40 in a rotating state is decelerated or stopped, and the rotation of the rotor 40 in a stationary state is prevented.

  When electric current is supplied to the coil 79, the brake 70 pulls the holding member 76 in the coil 79 to separate the friction material 74 and the brake pad 44. That is, the holding member 76 is positioned at the first position. Thereby, the rotor 40 can be rotated.

[Motor arrangement]
Next, the arrangement of the motor 20 (first motor) having the above configuration will be described. FIG. 6 is a diagram illustrating an internal configuration of the base portion and the turning portion. FIG. 7 is a diagram illustrating the arrangement of the motors in the turning unit.

  As shown in FIG. 6, the first motor 20 is accommodated in the turning unit 5 and fixed to the turning unit 5. Specifically, the first motor 20 is disposed such that the first surface 30a of the casing 30 faces the installation surface. That is, the motor 20 is disposed in the turning unit 5 so that the brake 70 faces upward. The first motor 20 is fixed to the turning unit 5 so that the output shaft Ax and the first shaft Ax1 are coaxial. Thereby, the first motor 20 rotates together with the turning unit 5. The brake 70 of the first motor 20 is disposed on the casing 30 in a range between the first axis Ax1 and the reference line LS. More specifically, the brake 70 is located on a straight line connecting the first axis Ax1 and the reference line LS.

  The first motor 20 is connected to the speed reducer 15. The reduction gear 15 is disposed on the base 3 and is fixed to the base 3. The input shaft of the speed reducer 15 is coaxial with the output shaft Ax of the first motor 20. That is, the output shaft Ax of the first motor 20 and the input shaft of the speed reducer 15 are coaxial with the first shaft Ax1.

[Function and effect]
As described above, in the motor 20 of the robot 1 according to the present embodiment, the casing 30 has a shape in which the dimension in the output axis Ax direction is smaller than the dimension in the direction substantially perpendicular to the output axis Ax, that is, a flat shape. ing. Moreover, the brake 70 is arrange | positioned in the position shifted | deviated from the output shaft Ax. Thus, the motor 20 in which the shape of the casing 30 is flattened and the brake 70 is arranged offset with respect to the output shaft Ax is employed, and the motor 20 is arranged so that the output shaft Ax is parallel to the first shaft Ax1. By arranging in the position, the dimension (height dimension) in the direction along the first axis Ax1 of the swivel unit 5 in which the motor 20 is accommodated can be reduced. Therefore, the contact between the first arm 7 and the swivel unit 5 can be avoided, and the second swing angle θ2 of the first arm 7 can be enlarged. As a result, it is possible to expand the operating range while suppressing an increase in the size of the apparatus.

  In the present embodiment, the first motor 20 is fixed to the turning unit 5 and rotates together with the turning unit 5. With this configuration, even when the turning unit 5 is turned, the positional relationship between the first motor 20 and the turning unit 5 does not change. Therefore, it is possible to avoid complication of cable wiring and the like in the turning unit 5.

  In the present embodiment, the first motor 20 is configured so that the output shaft Ax and the first shaft Ax1 are coaxial, and the first surface 30a opposite to the second surface 30b of the casing 30 faces the installation surface. Has been placed. The first arm 7 is swingable to a first swing angle θ1 in the first direction D1 with respect to a reference line LS passing through the second axis Ax2 in a direction substantially perpendicular to the installation surface. It can be swung to a second swing angle θ2 in a second direction D2 opposite to the first direction D1 with respect to the reference line LS. When viewed from the direction along the second axis Ax2, the first axis Ax1 is located on the second direction D2 side with respect to the reference line LS. The brake 70 of the first motor 20 is disposed on the casing 30 in a range between the first axis Ax1 and the reference line LS. According to this configuration, since the brake 70 is disposed on the first arm 7 side, the height of the first arm 7 side corresponds to the brake 70 in the turning unit 5 that houses the first motor 20. The height dimension of the part away from the first arm 7 can be suppressed. Thus, when the first arm 7 swings in the second direction D2, the contact between the first arm 7 and the swivel unit 5 can be avoided, so that the second swing angle θ2 can be increased. As a result, the operating range can be expanded.

  In the present embodiment, the robot 1 includes a speed reducer 15 that is connected to the first motor 20 and has an input shaft that is coaxial with the output shaft Ax. The reduction gear 15 is fixed to the base 3. According to this structure, the enlargement in the width direction of the turning part 5 and the base 3 can be suppressed. As a result, the interference radius at the time of turning of the turning unit 5 can be reduced.

  The present invention is not limited to the above embodiment. For example, in the above-described embodiment, the configuration including the first arm 7 and the second arm 9 has been described as an example, but an arm may be further connected to the second arm 9.

  In the above embodiment, an example of the configuration illustrated in FIG. 5 has been described for the motor 20, but the configuration of the motor 20 is not limited thereto.

  DESCRIPTION OF SYMBOLS 1 ... Robot, 3 ... Base, 5 ... Turning part, 7 ... 1st arm, 15 ... Reduction gear, 20 ... Motor (1st motor, 2nd motor), 30 ... Casing (body part), 30a ... 1st 1 surface (other surface), 30b ... 2nd surface (1 surface), 70 ... brake (protrusion part), Ax ... output shaft, Ax1 ... 1st axis, Ax2 ... 2nd axis, LS ... reference line.

Claims (4)

The base,
A revolving part that is pivotally attached to the base and that revolves around a first axis in a direction substantially perpendicular to an installation surface on which the base is installed;
An arm swingably attached to the swivel unit and swinging about a second axis horizontal to the installation surface;
A first motor housed in the swivel unit and operating the swivel unit around the first axis with respect to the base;
A second motor that moves the arm around the second axis with respect to the swivel unit;
With
The first motor is
A body portion whose shape in the output shaft direction is smaller than that in a direction substantially perpendicular to the output shaft;
A robot that protrudes from one surface of the main body along the output shaft direction and is disposed at a position displaced from the output shaft.   The robot according to claim 1, wherein the first motor is fixed to the turning unit and rotates together with the turning unit. The first motor is arranged such that the output shaft and the first shaft are coaxial, and the other surface opposite to the one surface of the main body is opposed to the installation surface.
The arm is swingable to a first swing angle in a first direction with respect to a reference line passing through the second axis in a direction substantially perpendicular to the installation surface, and with respect to the reference line. The second direction opposite to the first direction can swing to a second swing angle,
When viewed from the direction along the second axis, the first axis is located on the second direction side with respect to the reference line,
The robot according to claim 2, wherein the protruding portion of the first motor is disposed on the main body in a range between the first axis and the reference line. A reduction gear connected to the first motor and having an input shaft disposed coaxially with the output shaft;
The robot according to claim 1, wherein the speed reducer is fixed to the base.

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